This invention relates to digital printing, and more particularly to cluster printing systems. Most print output devices, such as copiers, printers, facsimile machines and other similar print output devices (collectively referred to as “printers”), may be used with a wide variety of output media. Indeed, conventional printers typically include one or more media trays that accept many different media types, sizes, colors and weights. When a user submits a print job to such a printer, such as by selecting a “Print” function from within a word processing, spreadsheet, page layout, or other software application, the application typically calls a print driver that permits the user to specify numerous print output specifications, such as a desired media for the print job. A user interface on conventional print drivers typically includes pull-down menus that allow the user to select a specific media tray or specific media attributes for printing the print job. For example, if a user knows that desired media are loaded in Tray 2 of the printer, the user may select Tray 2 from a media tray pulldown menu, and the print job will be printed on media extracted from Tray 2. Alternatively, a print driver may allow a user to specify media attributes, such as type, size, color or other attribute rather than specifying a particular media tray. For example, if any of a printer's media trays includes Letterhead paper, a user may specify Letterhead from a media type pulldown menu, and the print job will be printed on media extracted from a tray that includes Letterhead.
For conventional office or home printers, the number of different media trays and attributes is usually small, and the media specification process is usually quite straightforward. Indeed, most office or home printers include only a few media trays, and typically use only a handful of different media attributes. For commercial print shop printers, however, the number of different media sources and attributes may be quite large. Indeed, a commercial print shop printer may have many different media trays that may be loaded with media having a large number of different attributes. For example, a printer used in a print shop may have six media trays that each may be loaded with media having any of twenty different colors, ten different sizes, five different weights, and three different hole-punching styles.
If a printer supports many different media attributes, the printer may provide pulldown menus for selecting media attributes, such as media size, type, weight, color, and other attributes. Thus, a user may find it quite time consuming to specify each media attribute for every print job. To simplify this selection process, some previously known print systems include a paper catalog for media selection. An exemplary previously known paper catalog is illustrated in FIG. 1. Paper catalog 10 is a two-dimensional array that associates one or more media names 12 with a corresponding set of media attributes 14. In the illustrated example, media names 12 are associated with attributes “Size,” “Color,” “Weight” (in grams per square meter, “g/m2”), “Type,” and “Mode.” A system administrator typically creates the various entries in the paper catalog for commonly used media. Once the paper catalog is created, a user may specify desired media for a print job by selecting any one of the entries in the catalog via a print driver or other job submission means, such as a proprietary downloader or Web submission means.
For example, a paper catalog may include a first entry named “Letter” to designate media that are 8.5×11″, white, 75 g/m2, plain, single sided or double sided, and capable of being hole-punched, and a second entry named “Letter Pink” to designate media that are 8.5×11″, pink, 75 g/m2, plain, single sided or double sided, and capable of being hole-punched. For print systems that use a paper catalog, the media selection process is simple. Rather than navigating through numerous media attribute pulldown menus and submenus, a user instead only needs to select a desired media name from a single paper catalog pulldown menu. When the print job is submitted to the printer, the media attributes associated with the selected media name will be communicated to the printer, and the printer will extract media from the appropriate tray that includes media having those attributes. Paper catalogs therefore have greatly simplified the media selection process.
In addition to improvements in the media selection process, print systems have also advanced in other ways in recent years. Indeed, print technology has advanced to provide “cluster printing,” in which multiple printers may be coupled together in a network. In particular, cluster printing systems may be used to couple multiple printers together to form “virtual printer groups.” One exemplary cluster printing system is Velocity™ workflow software, including the Velocity Balance Server™, licensed by Electronics for Imaging, Inc., Foster City, Calif. Velocity software may be used to couple many printers together, regardless of brand and model, to appear as a single virtual printer group on a network. Velocity software can load balance a single “long” print job among multiple printers, split color from black-and-white pages in the same document, route a print job to the best available printer based on the number of pages and other characteristics, send a print job to an alternate printer if a currently selected printer is out of paper or toner or if there is a paper jam, and automatically send certain types of jobs to specific printers, based on specified criteria such as media characteristics, finishing options and device capabilities.
Referring to FIG. 2, an exemplary previously known cluster printing system is described. Cluster printing system 20 includes one or more client devices 22a-22c coupled to server 28, which is also coupled to one or more printers 32a-32d. Client devices 22a-22c may be personal computers, laptop computers, handheld computers, computer workstations, personal digital assistants, cell-phones, fax machines, or any similar device that may be used to provide print jobs 24a-24c, respectively, for printing. Client devices 22a-22c may be coupled directly to server 28, or may be coupled to server 28 via a communications network 26. Server 28 may be a personal computer, laptop computer, handheld computer, computer workstation or any similar device that includes software and/or hardware that provides cluster printing capabilities.
Printers 32a-32d may be printers, copiers, fax machines, laser printers, plotters, inkjet printers, wide format printers, or other similar printers that may be used to provide print output 34a-34d, respectively. Printers 32a-32d may be the same make and model, or may include more than one make and model of printer. For example, printer 32a may be a 12 page per minute (“ppm”) black and white printer, printer 32b may be a 50 ppm black and white printer, printer 32c may be a 32 ppm color printer, and printer 32d may be a 75 ppm color printer. Printers 32a-32d may be coupled directly to server 28, or may be coupled via network 30. Networks 26 and 30 each may be a local area network, wide area network, wireless network, the Internet, or any similar network. Networks 26 and 30 each may be a single network or may include multiple networks, and the two networks may be the same network.
A user of any of client computers 22a-22c, such as client computer 22a, may create virtual printer clusters that include various combinations of printers 32a-32d. For example, a user of client computer 22a may form a first virtual printer group including printers 32a and 32b, a second virtual printer group including printers 32c and 32d, a third virtual printer group including printers 32b, 32c and 32d, and so on. A corresponding print driver for each virtual printer group may then be installed on client computer 22a, and print job 24a may then be submitted to any of the virtual printer groups by specifying the desired virtual printer group from a printer selection menu.
One problem associated with previously known cluster printing systems, however, pertains to media selection. Because cluster printing systems may be configured with printers that include more than one make and model of printer, the constituent printers in each virtual printer group may not use a single media selection process. For example, some printers in a cluster printing system may provide media selection via a paper catalog, other printers may provide media selection via media tray pulldown menus, and still other printers may provide media selection via media attribute pulldown menus. Further, even if several printers provide media selection via paper catalogs, the printers may not use the same paper catalog. Thus, printer 32a may provide media selection via a first paper catalog, printer 32b may provide media selection via a second paper catalog that differs from the first paper catalog, printer 32c may provide media selection via media tray pulldown menus, and printer 32d may provide media selection via media attribute pulldown menus.
Previously known cluster printing systems typically address this issue by providing print drivers that include a superset of media selection options for all printers in the corresponding virtual printer group. Thus, a print driver for a virtual printer group that includes all four printers 32a-32d may permit media selection using the first paper catalog, the second paper catalog, the media tray pulldown menu and optionally other media attribute pulldown menus, such as a media type pulldown menu. A problem may occur, however, if these different media selection techniques do not use a consistent convention for designating media. For example, printer 32a and printer 32b each may have three paper trays, with the first, second and third trays of each printer loaded with white paper having weights of 80 g/m2, 75 g/m2 and 70 g/m2, respectively. The first paper catalog may classify theses media weights as “Heavy,” “Medium,” and “Light,” respectively, whereas the second paper catalog may classify the exact same media weights as “80 g/m2,” “75 g/m2,” and “70 g/m2,” respectively. If a user submits print job 24a to the virtual printer group and selects an entry from the first paper catalog that specifies Medium weight paper, the entire print job will be sent only to printer 32a, because only printer 32a recognizes a media weight designated as Medium. This is true even though printer 32b is a faster printer that has the exact same media as printer 32a, and could print some or all of the print job.
In view of the foregoing, it would be desirable to provide methods and apparatus for simplifying and unifying the media selection process for cluster printing systems.
It further would be desirable to provide to provide methods and apparatus for providing a universal paper catalog for cluster printing systems.